Instead of all the American languages being polysynthetic by amalgamating words, we find in America many mixt forms, and even the pure monosylabic: while the amalgamation of words prevails more or less in Europe and Africa; chiefly in the Bask, Italian dialects, Greek, Berber and other Atlantic dialects, the Negro languages, those of Caffraria, the Sanscrit and all the derived languages.
"The American Nations, Vol. I."
C. S. Rafinesque
Both languages are extremely artificial in their grammar, and allow an accumulation of pronominal affixes at the end of verbs, surpassed only by the Bask, the Caucasian, and those American dialects that have been called polysynthetic.
"Lectures on The Science of Language"
Max Müller
The languages of the Huron-Iroquois family belong to what has been termed the polysynthetic class, and are distinguished, even in that class, by a more than ordinary endowment of that variety of forms and fullness of expression for which languages of that type are noted.
"The Iroquois Book of Rites"
Horatio Hale